This was an "accident," a play where the weak accidentally killed a strong enemy.
Alger's strength was quite good; both his sword skill and physical fitness were considered extremely excellent among all the remaining Trainees.
Therefore, to complete this play, Liens needed to be more serious.
Killing Alger was not difficult for Liens.
This was partly due to his overwhelming advantage in sword skill, and also because he often used Alger for sword practice, giving him a good understanding of his opponent's situation.
After four months of brutal training, the surviving Trainees were no longer what they used to be; the Trainees ranked higher were now even stronger than ordinary guards.
So now, he chose those top-ranked Trainees as targets for "sword practice."
Of course, when he truly wanted to kill, Liens wouldn't care about the difference between guards and Trainees.
Any living being in front of him was a potential target; only death could stop the killing.